unexplained

adj.

未作解释的；未经说明的；不清楚的；

1. He died in unexplained circumstances.
   他死因不明。
2. His unexplained absences fed our suspicions.
   他的无故缺席引起了我们对他的怀疑。
3. There are too many unexplained mysteries in the world.
   世界上有太多解不开的谜。
4. Truthfully, there have been some unexplained occurrences around the house.
   老实说，这房子的周围发生过一些无法解释的现象。

Fever of Unexplained Origin
Petersdorf RG, Beeson PB. Fever of unexplained origin: report on 100 cases
Population-based study of the incidence of sudden unexplained death in epilepsy
Sudden unexplained death: heritability and diagnostic yield of cardiological and genetic examination in surviving relatives
Prospective evaluation of unexplained chronic liver transaminase abnormalities in asymptomatic and symptomatic patients.
Sudden arrhythmic death syndrome: a national survey of sudden unexplained cardiac death
Altered vagal and intestinal mechanosensory function in chronic unexplained dyspepsia
Underlying causes and long-term survival in patients with initially unexplained cardiomyopathy
Outcome of patients with nonischemic dilated cardiomyopathy and unexplained syncope treated with an implantable defibrillator
Defective production of both leukemia inhibitory factor and type 2 T-helper cytokines by decidual T cells in unexplained recurrent a...